The e-commerce giant announced a three-year pact yesterday with pay-TV service Epix to add thousands of movies such as “The Avengers” and “The Hunger Games” to its Prime instant video service.

The deal gives Amazon access to content that had been exclusive to Netflix. Exclusivity on Netflix’s $950 million, five-year deal with Epix has ended, with payment lower in the three remaining non-exclusive years.

Amazon has been beefing up its catalog of movies and TV shows that are available to its Prime service and last month added NBC Universal programming.

With between 8 million and 10 million Prime members, who pay $79 a year for a package of perks that also includes free shipping, subscription fees likely all go to paying Hollywood for movies, analysts said.

“If you were to look at Amazon Prime streaming as a stand-alone business it would operate at a loss,” said Barclays analyst Anthony DiClemente. “That’s looking at it in isolation, but you have to look at it in the context of Amazon’s broader e-commerce business.”

Amazon has captured more than 20 percent of the tablet market with its Kindle Fire, and the devices are boosting digital sales. Amazon tablet buyers get a free month of streaming through Prime — all part of a broader strategy to lock users into the e-commerce ecosystem.

The Epix deal came just ahead of Amazon’s conference set for tomorrow to unveil a new line-up of tablets and e-readers.

Meanwhile, Netflix shares fell 6.4 percent yesterday to $55.93 as Wall Street digested the new blow to the streaming-video service.

“Netflix can only thrive if it has an unopposed playing field,” said Wedbush Securities analyst Michael Pachter. “The specter of competition means content costs go up and prices for consumers go down.”

While Netflix has 24 million subscribers, investors are concerned about heightened competition. At $79 a year, Amazon Prime works out to about $6.60 a month — cheaper than Netflix’s streaming service at $7.99 a month.

Now that Amazon is spending even more on content, the only way to make up the costs is adding subscribers. The company could offer access to its movie catalog to non-Prime subscribers — forgoing the free shipping incentive — for about $5 a month, Pachter said.